Dental instrument.



W. W. EVANS.

DENTAL INSTRUMENT.

APPLICATION FILED JUNE 10, 1912.

. 1,070,123. Patented Aug. 12,1913.

WITNESSES INVENTOR I g Home COLUMBIA PLANDGRAPH co., WASHINGTON, B. c.

UNITED STATES PATENT OFFICE.

WILLIAM W. EVANS, OF HAMILTON, VIRGINIA, ASSIGNOR TO THE S. S. WI-IITEDENTAL MANUFACTURING COMPANY, OF PHILADELPHIA, PENNSYLVANIA, A

CORPORATION OF PENNSYLVANIA.

DENTAL INSTRUMENT.

Specification of Letters Patent.

Application filed June 10*, 1912. Serial No. 702,777.

To all whom it may concern:

Be it known that I, WILLIAM W. EVANS, a resident of Hamilton, in thecounty of Loudoun and State of Virginia, have invented certain new anduseful Improvements in Dental Instruments; and I do hereby declare thefollowing to be a full, clear, and exact description of the invention,such as will enable others skilled in the art to which it appertains tomake and use the same.

This invention relates to improvements in dental instruments, and moreparticularly to registering devices for use in conjunction with dentalarticulators, the object of the invention being to provide simple andeflicient means adapted to be supported by the head of a patient andoperable to make records of the condyle paths when the jaws of thepatient are moved as in the act of mastication.

WVith this and other objects in view, the invention consists in certainnovel features of construction and combinations of parts as hereinafterset forth and pointed out in the claims.

In the accompanying drawings, Figure 1 is a perspective viewillustrating my improvements; Fig. 2 is a partial v1ew of the yoke andattached devices; Figs. 3 and 4: are

detail sectional views showing the mounting of the marking devices; Fig.5 is a view in section on line m-w of Fig. 2; Fig. 6 is an enlarged sideelevation of the head band and card frame; Fig. 7 is a section on liney-y of Fig. 6, and Fig. 8 is a section on line zz of Fig. 6.

1 represents a yoke which may be conveniently made of wire and isadapted to sustain a trial plate support 2 removably and adjustably butnormally rigidly secured thereto by means of a suitable clamp 3.

An adjustable head band 5 is provided and may be conveniently made ofthin sheet metal comprising two sections having sliding connection witheach other through the medium of a plate 6 having a guideway 7 toreceive the overlapping ends of the band sections.

At each end of the band 5, a frame 8 is located, and each frame isprovided with an offset arm or plate 9 lying in a plane parallel withthat of the frame 8 and inwardly of the same, said frame and arm orplate being connected by a part 10 disposed at right angles to both. Theframe 8 is made with an opening 11 and at the side edges, said frame isprovided with guides 12 for a card 13 on which a meridian line 14: isdrawn. The arm or plate 9 of each frame 8 is provided with an elongatedslot 15 and the head band 5 is provided at each end with an elongatednotch 16. Through these slots, the threaded shanks 17 of the knobs 18(the latter being made preferably of glass) pass, and these shanksreceive lever nuts 19. In this manner, the arms or plates 9 of theframes 8 are adj ustably attached to respective ends of the head band5,such adjust-able connection of the frames to the head band permittingtheir proper disposition to enable the operator to accurately locatesaid frames opposite the condyles of the patient. The openings 11 in theframes 8 will permit the operator to locate, with his finger, thecondyles of the patient and the knobs 18 entering the ears of thepatient will also assist in properly positioning the frames 8. In orderto assist the operator in disposing the frames 8 in horizontalpositions, said frames may be provided with spirit levels 24:.

Blocks 20 are adjustably secured to the arms 4 of the yoke, by means ofset screws. These blocks are provided with transverse threaded holes toreceive threaded rods 21, each having a suitable longitudinal mark orgroove 22 which acts as a guide to permit accurate adjustment of saidrods. Each adjustable rod 21 is made hollow to receive a spring-pressedpencil lead or point 23.

In using the device, the operator will place the band 5, with the frames6 attached to its ends, on the head of the patient so that the knobs 18will enter the patients ears. The model or trial plate having beenproperly disposed in the mouth of the patient, the operator will insertthe trial plate support 2 and after the latter shall have been properlyattached to the trial plate, the operator will adjust the yoke and theframes 8 until he can accurately locate the condyles by inserting hisfinger through the openings 11. The blocks 19 will then be adjusted onthe arms of the yoke until the pencil points in the transverse rods 21become disposed .in the plane of the condyles of the patient and thetrial plate support will be rigidly secured to the yoke, by means of theclamp 3. The distance between the plane of the condyles and the trialplate or model has now been determined, and by placing the rods 21 111the plane of the hinge connection between the two members of anarticulator,

the trial plate or model can be accurately placed in the articulator.The instrument having been applied to the patient as above described,the operator will insert the cards 13 into the frames 8 so as to coverthe open ings in the latter, the meridian line on said cards being thendisposed at right angles to the plane of the condyles. The patient willnow move his lower jaw as in the act of n'iastication, and the pencilpoints will mark the cards 13, and the lines thus made by the pencilpoints will be atan angle to the meridian line on the cards. Theoperator will ascertain the degree of the angle of the lines made on thecards, by means of a protractor, and he will then adjust the hingeconnections or artificial condyles of the articulator accordingly, thuscausing the lower member of the articulator to be capable of move mentsidentical with those of the lower jaw of a particular patient.

Having fully described my invention what I claim as new and desire tosecure by Letters-Patent, is

1. In a dental instrument, the combination with a yoke and a trial.plate support, of means independent of said yoke for supportingregistering cards coincident with the condyles of a patient, and markerson said yoke to mark said register cards when the lower j aw of thepatient is moved.

2. In a dental instrument, the combination with a face yoke and a trialplate support associated therewith, of frames having opei'iin'gs, meansindependent of said yoke for supporting said frames coincident with thecondyles of a patient, transverse rods adjustable on the arms of theyoke, cards provided with meridian lines, removably mounted in saidframes, and markers carried by said transverse rods.

3. In a dental instrument, the combination with a face yoke and a trialplate support associated therewith, of frames, adjustable meansindependent of said yoke for supporting said frames coincident with thecondyles of a patient, cards having me ridian lines, supported by saidframes, and markers adjustable on the arms of the yoke.

4. In a dental instrument, the combination of a head band, framesadjustably secured to the ends of said band, ear knobs adjacent to saidframes, a face yoke, a trial plate support associated with said yoke,cards mounted in said frames, and adjustable rods mounted adj ustably011 the arms of the yoke and carrying markers.

5. In a dental instrument, the combination with a yoke and a trial platesupport, of frames having openings, means for supporting said. framescoincident with the condyles of a patient, record cards having meridianlines, supported by said frames, leveling means on said frames, andmarkers supported by the yoke for making a record on said cards.

In testimony whereof, I have signed this specification in the presenceof two subscribing witnesses.

WILLIAM lV. EVANS.

l Vitnesses WILLIAM J. RUSSELL, H. A. CowAnn.

Copies of this patent may be obtained for five cents each, by addressingthe Commissioner of Patents, Washington, D. C.

